Stumbled onto Something Today

I have a rather large supply of once fired .223R Federal cases, courtsey of one of the local SWAT teams...Ive not loaded FC in the past that I can remember as Ive always had an abundant supply of Remington and LC brass..

However I NEVER turned down once fired brass unless its junk....I do quite a lot of reloading for friends, especially during the hunting season...I get some pork and venison in the barter.....SO...I figure using the FC brass is good to use for their consumption to fire and forget...

This morning, I deprime and size a batch of the FC .223 Rem and noticed the primer pocket appeared to be crimped...When I tried seating with my RCBS hand priming tool, I discovered quickly that I was right...I had to swage the primer pockets on all of them...

Ive not seen crimped primer pockets on commercial brass before. The SWAT team shoots FC Gold Metal Sierra Match King ammo and it isnt anything special order..This made me curious if Federal was using military grade brass for some of their loadings, so I decided to weigh and compare.

I selected at random 12 rounds of each FC, Remington, and LC cases..All deprimed and trimmed. After weighing, I threw out the high and low weight of each calculated for average and SD...

I was surprised that the Remington brass weighted significantly more than even the LC Military.. I was also surprised that the FMK's had the largest SD...

If I'm 'thunking' this right and If I were to reload these cases using the very same loading parameters for each, then the Remington cases should give the highest velocity/pressure...It has always been my understanding that military cases had thicker walls and thus should be downloaded to avoid excessive pressure.....

It's entirely possible the weight disparity is down at the web and not the wall. You are only talking about four grains in weight. I am surprised that you had such large variation in weight with the Federal brass, because I've always found FC brass to be much more consistent on paper than any other. I've just about quit buying WW brass because it's so crummy.

Friends410...Yeah, that is entirely possible...Maybe tomorrow I will check the water capacity....Plus, my test was on a rather limited number...I also found it interesting that the FC didnt score better as it is some of the very best factory fodder out there..The Gold Medal Match is awesome and even the American Eagle ammo outshoots most any other factory load Ive tried..

Some of the very best ammo (.308W) I have ever shot is the remanufactured Georgia Arms Match grade which uses the SMK bullet and LC brass..I was curious about the load, so I disassembled a few rounds to see what was inside...I measured the cases and none were the same OAL... The powder charge was +- 1/10 grain and appeared to be Varget or 4895...Been reloading for nearly 50 years and learn something new everyday...

It has always been my understanding that military cases had thicker walls and thus should be downloaded to avoid excessive pressure...

Click to expand...

Your understanding is correct for 308/7.62 and 30-06, but not correct as far as the 223/5.56 is concerned. This is one of those myths that got started long ago that will probably never die.
This is from Sierra.The conventional wisdom to reduce loads with military brass is familiar to most reloaders and is generally good advice. The rationale here is that the military cases tend to be somewhat thicker and heavier than their civilian counterparts, which in turn reduces capacity and raises pressures. This additional pressure normally requires a one or two grain reduction from the loads shown in most manuals or other data developed with commercial cases. While this is most often the situation with both 308 Winchester and 30-06 cases, it is less true with the 223 brass. We have found that military cases often have significantly more capacity than several brands of commercial brass. Again, take the time to do a side-by-side comparison of the cases you are working with and adjust your load as needed. There may be no need for such a reduction with the 223. Know your components and keep them segregated accordingly.

Outstanding information, Steve...Thank you.. As stated in previous post, I been reloading for the past 50 years and I learn new stuff every day.,..

Ive only been reloading .223 for about the last 5-6 years and have become quite attached to finding what my rifles can do with this round...A lot more fun to shoot and more economical than the .308W...Since I rarely shoot further than 5-600 yards, .223 does just fine.